performance - PostgreSQL - Are BEFORE triggers more efficient then AFTER triggers? -

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I read in a bus, before being triggered "more effective" before triggering: < Blockquote>

If you have no special reason to trigger before or after, then it is more efficient than before, because information about the operation is not saved until the statement ends.

I do not know what this is true or what it means for me. Can anyone illuminate me? Is it just a homeopathic performance improvement?

PostgreSQL of MVCC architecture, each operation Increases the amount of data recorded in the system, even DELETE .

So if you need to check your input and if the check fails then roll back the transaction, you can do better before saving input data.

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